# Copyright 2025 ApeCloud, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


class FlowError(Exception):
    """Base exception for flow engine"""

    pass


class CycleError(FlowError):
    """Raised when a cycle is detected in the flow graph"""

    pass


class TypeMismatchError(FlowError):
    """Raised when input/output types don't match"""

    pass


class NodeNotFoundError(FlowError):
    """Raised when a node is not found"""

    pass


class ValidationError(FlowError):
    """Raised when input validation fails"""

    pass
